Environmental and Sustainability Indicators (Jun 2024)
Optimizing crop nutrition in rainfed castor cultivation for higher productivity, energy efficiency, and reduced carbon footprint
Abstract
Nutrition plays a key role in achieving higher crop productivity. Whereas, rainfed cropping greatly suffers due to imbalanced crop nutrition. Especially, crops like castor mostly face the utmost climatic and edaphic distress as it is predominantly cultured in poor soil of rainfed regions. Therefore, to know the performance of the rainfed castor to balanced nutrient management modules, a field experiment was conducted for two consecutive Kharif seasons in 2020 and 2021. Crop responded favorably to the balanced nutrition. We observed substantial improvement in seed yield (44%), oil yield (49%), gross return (54%), and net return (133%) with the application of the recommended dose of fertilizer (RDF) + 20 kg ZnSO4 ha−1 along with foliar spray of 2% water soluble complex fertilizer (WSCF) @ 40 days after sowing (DAS). + over soil application of RDF and 125 % RDF. Due to better crop response in terms of growth and yield, rainwater use efficiency (RWUE), partial factor productivity (PFP), and agronomic efficiency (AE) were also higher with RDF + 20 kg ZnSO4 ha−1 along with a foliar spray of 2% WSCF @ 40 DAS. Application of 125 % RDF showed enhanced energy consumption (11429 MJ ha−1). While RDF +20 kg ZnSO4 ha−1 along with a foliar spray of 2% WSCF @ 40 DAS showed 45% and 17% higher energy output compared to the RDF and 125% RDF. Due to higher energy output, the same treatment exhibited 55 and 21 % higher net energy gain over RDF and 125% RDF, respectively. As per as the carbon (C) footprint is concerned, RDF + 20 kg ZnSO4 ha−1 along with a foliar spray of 2% WSCF @ 40 DAS was observed to be slightly C expensive with 8 % higher carbon input due to higher rates of manpower and machinery utilized. However, it displayed higher C output (45%), net C gain (56%), C efficiency ratio (33%), C efficiency (37%), and C sustainability index (32%) indicating efficient C management over RDF. Overall, RDF +20 kg ZnSO4 ha−1 along with foliar spray of 2% WSCF @ 40 DAS appeared to be the productive, profitable, energy efficient, and even favorable in respect of C footprint than soil application of RDF or 125 % RDF.
